The Honourable Thomas Fitzmaurice (July 1742 - 28 October 1793) was a Member of Parliament for Calne from 1762 to 1774, and then for Chipping Wycome until 1780.
His elder brother William was an MP before he inherited the family titles on his father's death in 1761; he later became Prime Minister of Great Britain in 1782 and was created Marquess of Lansdowne in 1784.
After William was elevated to the House of Lords, he arranged for Thomas to replace Isaac Barré as Member of Parliament for Calne in December 1762.
[4] Thomas represented Calne unopposed until 1774, when he moved to Chipping Wycome, another rotten borough controlled by his brother, exchanging seats with Barré.
However, whereas William eventually became Prime Minister of Great Britain, Thomas Fitzmaurice had left Parliament by 1780, replaced in Chipping Wycome by Charles Stanhope.